Hello TI team,
We are using TPS65988 in one of our designs. We have two Type-C ports on boards, in which Port A will be used as Power sink(UFP) only and it has no data role and Port B will be used as DRP port( with both power sink and source capabilities) and supports USB 2.0.
Attached the block diagram and schematics of the PD section for better understanding.
We are using internal power paths of TPS65988 to sink power to the board and external power path is provided only for Port B to source power to any connected slave device when acting like DFP.
We want to meet the below requirements:
1. When Type-C adapters are connected to both ports, only one of the internal power path switches should close with the highest PD power contract.
2. External power path provided for Port B is controlled by GPIO17. This path should close only when a slave device is connected to Port B(Port B acting as DFP) and VCC_5V0 present on board.
3. Since Port B supports USB 2.0, the Data role of the port B should be informed to the Host controller.
Attached the project file which we are currently using.
We are facing the below problems:
1. External power path is meant only for sourcing when Port B acts as DFP. But when a Type-C power adapter is connected to Port B, GPIO17 is going high, closing the external path and power rails VBUS_TYPEC2 and VCC_5V0 are getting shorted, which is not desired.
2. Since Port B supports USB 2.0, how to convey the Data role of the port B to the Host controller? Planning to use one of the GPIO of the TPS65988. What should be the GPIO mapping event for this?
Please review the project file attached and do let me know the corrections that need to be done.
Thanks,
Anushree
